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Rye Starter Acetone Smell: When is it ok, and when is it bad?

Kashipan's picture
Kashipan

Rye Starter Acetone Smell: When is it ok, and when is it bad?

I've just tried starting my first sourdough starter!  I'm using a recipe that requires just a small amount of rye flour and water, and started it last Monday night, on a 24 hour feeding schedule.  The last time I fed it (increments of 30ml of water to 30g of rye flour, discarding 1/3 each time) was last night at 7pm.  Today is day 7.  The starter is doubled by the time I wake up in the morning, and just kind of hangs out until I feed it again in the evening.  It only falls a little bit, stays full of bubbles and develops no hooch.  There's no mold in it.  Color looks fine.  The consistency is that of thick oatmeal - not too wet, but easy to stir.

But the smell...I can't tell whether it's bad or good.

I don't usually stick my nose in it until it's time for its next feeding.  By that time, I definitely smell some alcohol, like the nail polish remover acetone thing lots of people talk about, but I also smell yeast and even some deep, dark, fermented fruity scent down there, like wine.  The smell is not overpowering, vomit inducing, or even filling up the house (I keep the starter on a dark shelf, room temperature, which hovers around 25C-27C this past week), but I definitely get a strong noseful when I first open it up.

Once I stir in the new flour and water, the smell just kind of goes back to the smell of wet rye flour and a little ferment.  Not strong.

I've been searching all over the internet, and am increasingly frustrated to see some people say that the second it smells like nail polish remover to dump it immediately and start over, while others say it just means the starter is active, hungry, and to feed it again.  Still others say that a young, week old starter will be full of all kinds of smells, and to just keep on as it is and let it develop for another week or longer.  Another place said that it's the rye flour that creates that kind of smell, compared to other flours.

Is the acetone smell ok in moderation?  When does an acetone smell start meaning your starter needs to be discarded?  I'm really confused and wondering how to proceed.  My gut tells me that it's the hungry starter acetone smell, but I really need your opinions, too.  I've got 10 hours to wait til the next feeding, and I can smell the acetone, alcohol, deep dark fruity fermenty yeast combination clearly now, in my puffed up, bubbly starter.  Does this sound ok to you?

 

tchism's picture
tchism

Acetone smell is an indication to me that it's not getting fed often enough or is being kept somewhere too warm. I feed mine every 12 hours and it's kept in the house that's no warmer than 75F. 

 

 

cranbo's picture
cranbo

Agreed with tchism. Acetone smell means there's no food left for your starter. Rye will grow more quickly than a whole wheat or all-purpose flour starter, so you need to feed more often and keep at moderate temps. 

PetraR's picture
PetraR

I would think that you need to feed your Starter more often, say 2x a day.

I have the same smell when my Rye and/or Wheat Starter sits on the counter and it is warm and it needs food.

 

Mini Oven's picture
Mini Oven

Take out a teaspoon of ripe starter and place the rest of the starter covered into the refrigerator.  (Dump or flavour something later, for now it is a "back up" starter.)  

Take that teaspoon of starter and add 30g of water and 40g of rye flour to make a soft paste.  Then let it ferment.  Gently touch it in 8 to 12 hrs and see if it deflates.  If it deflates, repeat the feeding every 8 to 12 hrs.  If it is still rising, let it peak out and give it a few hours of fermenting before feeding. If you want to use for bread baking go ahead but always save some of it to feed and maintain.  With each feeding you should see it fermenting and ripening sooner.  peaking in about 6 to 8 hrs. with those feed ratios.  The starter can easily wait until 12 hrs to be fed again.  You can play easily with the water amounts to speed or slow down fermentation.  

If you find an acetone aroma coming back, add a little lemon juice to the feed water for a several days.  

AbeNW11's picture
AbeNW11 (not verified)

...it is ready to bake with. When you're at this stage, unless you're baking at least every other day, it should be kept in the fridge.

Keeping it out too long without feeding it isn't good.

My schedule is (and I bake once a week):

1. Saturday afternoon take out of fridge.

2. Saturday night feed.

3. Sunday morning take out enough to use in my baking.

4. Return to fridge.

5. Next Saturday afternoon repeat process.

Your starter sounds fine just needs some TLC. You'll notice when you feed it it will change to a sweet smell. This is good. If I were you i'd take off 3/4 and give it a good feed, Sourdough starters love really good feeds at least double, then stir down and keep about 60g in the fridge. Discard rest. Or you can always keep two going incase you're worried one might fail. I don't though.